The invention relates to a device for detecting knocking and for regulating an internal combustion engine.
So that an internal combustion engine can be optimally regulated, it is necessary to dependably detect so-called "knocking", which represents a critical operational state which can have a disadvantageous effect on the service life of the internal combustion engine. If knocking is detected, the ignition angle is normally adjusted, so that it is assured that knocking will be prevented during the following ignition processes.
In known devices for the detection of knocking, the sounds generated in the internal combustion engine are registered with the aid of so-called structure-borne noise sensors. The output signals from the sensors are processed and analyzed with the aid of a microprocessor.
A device for detecting knocking, operating in accordance with this method is known, for example, from DE-OS 44 21 950. With this known device the output signals are first preprocessed and then further processed with the aid of a neuronic network as well as a connected fuzzy logic device. If knocking is detected, ignition or fuel injection is affected in the customary manner in such a way that conditions are reestablished under which no knocks occur.
Although a signal preprocessing stage is provided by the device for detecting knocking known from DE-OS 44 21 950, which matches the provided by the knocking sensors to the adjoining neuronic network as well as the fuzzy logic, no information can be found as to how the signal preprocessing stage is to be designed.